1. Field of the Invention
The present invention relates to a rear body structure for a vehicle, particularly a body structure around a rear floor.
2. Description of the Related Art
Japanese Unexamined Patent Publication No. 2000-255457 discloses a rear car body structure including a side sill provided on an outer side of a vehicle transverse direction and extended substantially in a straight manner in a vehicle longitudinal direction, and a rear side member connected to a rear portion of a side sill inner of the side sill and extended substantially straight in the vehicle longitudinal direction.
In foregoing rear car body structures, a rear portion of a rear side member is extended rearward from a transversely inner part of an offset portion of the rear side member in a vicinity of a front part of a rear wheel house. Consequently, impact force of a rear end collision is not smoothly transmitted from the rear side member to the side sill inner, breaking off the rear side member from the offset portion. An increase in thickness of a plate of the rear side member to prevent such breakage results in weight increase and poor press formability.
It is an object of the present invention to provide a rear vehicle body structure smoothly transmitting impact force of vehicle rear end collision from a rear side member to a side sill inner without increasing the plate thickness of the rear side member.
An aspect of the present invention is a rear vehicle body structure comprising: a rear side member including a front portion in front of a rear wheel house, extending in a vehicle longitudinal direction, a rear portion disposed on a transversely inner side of the front portion, extending in the vehicle longitudinal direction, and having a first wall on a transversely outer side thereof, and a middle portion having a second wall continuously provided from a front end of the first wall of the rear portion to a transversely outer rear end of the front portion; a longitudinally extending side sill inner, a rear portion of which is connected transversely outside the front portion of the rear side member; and a rear floor connected onto the rear side member and the side sill inner, wherein the rear portion of the side sill inner comprises a third wall configured to be accommodated within width of the rear side member to connect a bottom portion of the rear side member with the rear floor, and wherein the third wall of the side sill inner has, on its rear end, a flange portion configured to be fixed to the rear side member at a vicinity of a transition point from the first wall to the second wall, on substantially the same plane as the third wall.